The present invention relates to coaxial-structure filters and more particularly to the construction of the coaxial resonant cavities contained therein.
This invention is particularly, but not exclusively, useful for the design of microwave filters. The principles disclosed herein, however, may be applied to other microwave devices that employ coaxial resonant cavities.
Several drawbacks are encountered in the course of manufacturing coaxial resonators. Foreshortened coaxial resonators typically incorporate a flat cover and thereby require the resonator posts to be machined below the level of the resonator's outer wall. This is an inconvenient and costly multiple-step machining process.